L'eau rendue flot 15/06/2020
I have already used such a US QWERTY keyboard as a student especially for Matlab then, which came after APL (check about IBM 1130, IBM 5100 (5150 = original PC)). Then I have known of the Model M for the last few years.
Given the ANSIISO mechanical layout (optimised for right-handed people), this mechanical keyboard is marvellous : comfortable*, durable owing to its elegant simplicity and handmade in a Western country.
It is a chance to find new still in 2020 the keyboard talon (+3 keys of 1995) and to support the perpetuation of this know-how and IBM's R&D in ergonomics since they entered the typewriter market nearly a century ago...
Once purchased, it shows visible quality and robustness: very well packed and no problem during shipping... feet are soft to turn if you need and you have the 2-part keycaps... no concern at all!
+ The modifier keys on the right are logically re-ordered. That is, from the space bar : GUI shell, Alt (Application menu in ANSI QWERTY (but Alternate graphics in ISO AZERTY)), item (contextual menu), Ctrl (control character for command whether alone or in combination with Alt).
APL symbols are... (Big) Blue, of course... and so are lock LEDs either! = One's needs white lighting (so not coloured RGB LED) during day to appreciate these bicolor keys with Pearl background (colour more complementary than grey)... I have not seen any discrepancy with respect to the Dyalog US APL layout.
*Even if I am accustomed to low-travel scissor on rubber-dome switches keyboards too, now I understand how much typewriters could exist and sell (with scarce use of the Backspace key): I make less typographic mistakes with this Model M no matter when the beast of typing productivity is unleashed out of a pseudo-princess world (but in such one back in 1985 as Model M was considered silent at its release) even feeling using the Force or kind of it with tact(-ile feedback) - no excess of course mais c'est la folie quand mme ! That is I am not prevented from playing (with an instrument, not a game) more forte than piupiano (on the low-profile) regardless in AZERTY or QWERTY in order to reach my best speed writing the part and reading it. My fingers bounce back and I can also retype a key before releasing it completely like with a repetition lever (double escapement action).
In fact, this way, the delay to retype should be shorter as the spring is no longer buckled but shorter than when the key is completely released... thus forcing more the hammer back.